Cristiano Ronaldo's UEFA Champions League debut with Juventus came to an abrupt end when the prolific forward was sent off in the 29th minute of the Bianconeri's Group H match against Valencia at the Mestalla on Wednesday.

Ronaldo was shown a straight red card by referee Felix Brych for violent conduct after a tangle with Valencia centre-back Jeison Murillo in the box. Juve's club-record signing left the pitch visibly upset.

B/R Football @brfootball

RED CARD. 🔴 https://t.co/KDSULHvK2E

Bleacher Report Live @brlive

How Ronaldo got a red card 😳 https://t.co/AzTJJaWC81

The incident marked an unwanted first for a player who has traditionally owned this tournament:

OptaJoe @OptaJoe

1 - Cristiano Ronaldo has received his first red card in the Champions League in his 154th appearance in the competition. Off.

Ronaldo's dismissal resulted in some having fun at the five-time Champions League winner's expense:

Goal @goal

He can't believe it!
Cristiano Ronaldo has been sent off for Juventus and is in tears 😱#UCL https://t.co/TnqnlyOZA9

Paddy Power @paddypower

Cristiano Ronaldo has been sent off for Juventus.
*Ronaldo fans on Twitter*
'How many CL red cards has Messi got? Eh? Ronaldo is the goat!'

However, not everybody was impressed with the decision:

Adam Digby @Adz77

Cristiano Ronaldo just got a red card for shouting at a defender for diving. Game’s gone.

One thing beyond dispute was how comfortable Juve appeared with Ronaldo on the pitch. The Bianconeri had pushed the hosts back and were posing a consistent threat.

Juve were already hampered by midfielder Sami Khedira needing to be withdrawn. Yet manager Massimiliano Allegri will feel there is some justice after Miralem Pjanic put the visitors into the lead from the penalty spot in first-half stoppage time.

Allegri's squad is deep, experienced and pragmatic enough to win without Ronaldo, but the former Real Madrid man was supposed to make the difference between progress and actually winning this tournament.

A suspension means Ronaldo could miss subsequent group games against Young Boys, as well as a double-header against old club Manchester United.

Missing those matches will further stall what has been a relatively slow start to life in Turin for Ronaldo. The powerhouse No. 7 has scored twice in four Serie A matches so far.